Chris H
master of boobies
Renault fitted the 16V's with an immobiliser, to operate this immobilsier you have a key. Its either on or off.
However sometimes its on and no amount of key turning will switch it off.
This is the beast in all its glory,

Righty the key barrel is easy enough to see.
The short single wire is scotchlocked onto the glovebox door switch.
The long single wire (goes off scanner then comes back on at the top) feeds up through the dash and onto the induicator stalk, its scotchlocked into the red wire from the stalk cable.
The other wire, yes you are seeing correctly is cheap 2 core mains cable. This goes out through the bulkhead by the speedo cable to the aux fuse box on the inner nearside wing.
What is meant to happen.
The glovebox has a constant live feed to the switch, so when you open the glovebox the light inside comes on. When you arm the immobilser you let the current through the lock barrel so it goes to the indicator stalk wire, this lights up the indicators so you know its armed. When you close the glovebox the switch feed is cut so the indicator lights go out.
The other cable that goes to the engine bay goes to the fuel pump relay. The relay signal wire is cut and the brown and blue cable is crimped (yes really) on. So when the immobilser is off the circuit is complete but when you turn it on the circuit is opened (the lock barrel is just a simple switch).
This means the ignition will still fire, the engine will crank over but theres no petrol so the car will not start.
Its not a bad system when you think about it, you know when its armed, it stops the car starting and is very simple. But the main problem is the thing is very poorly fitted.
Poor fitting means its not only easy for some muppet to bypass but it means reliability problems.
The scotch lock connectors for the lights are not so important, the main problem is the crimping into the pump circuit.
The crimping is done in the engine bay in the aux fusebox, this can get water in it, which corrodes things a wiggle of the wire may allow it to start.
Also with the way the wire is routed (alongside the bonnet catch cable) the cable is easy to get caught and thus ripped out when changing the air filter etc etc.
If you want to retain the standard immobliser then I suggest you fit it properly. I also would recommend getting a proper CAT 1/2 system fitted, most insurers require this anyway.
So how do you fit it properly?
Well on the lighting side, the scotch locks are ok but if you want to do a pukka job then get the soldering iron out and cut the sheath on the wires solder then then tape them up.
The business side, I recommend getting a new cable (the 2 core mains is ok, it does the job), then routing it through the nearside wheelarch alongside the engine and lighting looms, these come out at the aux fusebox anyway so you willnot have any obvious wires on show. Get shot of the crimp terminals, solder the wire on and cover with heat shrink.
Another option is instead of going to the pump relay there you could splice it in somewhere else on the loom, inside the car or into a different circuit.
However sometimes its on and no amount of key turning will switch it off.
This is the beast in all its glory,

Righty the key barrel is easy enough to see.
The short single wire is scotchlocked onto the glovebox door switch.
The long single wire (goes off scanner then comes back on at the top) feeds up through the dash and onto the induicator stalk, its scotchlocked into the red wire from the stalk cable.
The other wire, yes you are seeing correctly is cheap 2 core mains cable. This goes out through the bulkhead by the speedo cable to the aux fuse box on the inner nearside wing.
What is meant to happen.
The glovebox has a constant live feed to the switch, so when you open the glovebox the light inside comes on. When you arm the immobilser you let the current through the lock barrel so it goes to the indicator stalk wire, this lights up the indicators so you know its armed. When you close the glovebox the switch feed is cut so the indicator lights go out.
The other cable that goes to the engine bay goes to the fuel pump relay. The relay signal wire is cut and the brown and blue cable is crimped (yes really) on. So when the immobilser is off the circuit is complete but when you turn it on the circuit is opened (the lock barrel is just a simple switch).
This means the ignition will still fire, the engine will crank over but theres no petrol so the car will not start.
Its not a bad system when you think about it, you know when its armed, it stops the car starting and is very simple. But the main problem is the thing is very poorly fitted.
Poor fitting means its not only easy for some muppet to bypass but it means reliability problems.
The scotch lock connectors for the lights are not so important, the main problem is the crimping into the pump circuit.
The crimping is done in the engine bay in the aux fusebox, this can get water in it, which corrodes things a wiggle of the wire may allow it to start.
Also with the way the wire is routed (alongside the bonnet catch cable) the cable is easy to get caught and thus ripped out when changing the air filter etc etc.
If you want to retain the standard immobliser then I suggest you fit it properly. I also would recommend getting a proper CAT 1/2 system fitted, most insurers require this anyway.
So how do you fit it properly?
Well on the lighting side, the scotch locks are ok but if you want to do a pukka job then get the soldering iron out and cut the sheath on the wires solder then then tape them up.
The business side, I recommend getting a new cable (the 2 core mains is ok, it does the job), then routing it through the nearside wheelarch alongside the engine and lighting looms, these come out at the aux fusebox anyway so you willnot have any obvious wires on show. Get shot of the crimp terminals, solder the wire on and cover with heat shrink.
Another option is instead of going to the pump relay there you could splice it in somewhere else on the loom, inside the car or into a different circuit.
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